diff --git a/crates/engine/src/cmd/fileio/tests.rs b/crates/engine/src/cmd/fileio/tests.rs index c523284ba..6236d281e 100644 --- a/crates/engine/src/cmd/fileio/tests.rs +++ b/crates/engine/src/cmd/fileio/tests.rs @@ -914,3 +914,34 @@ fn read_path_for_a_named_importer_stops_at_the_limit() { assert!(e.to_string().contains("larger than") && e.to_string().contains("drawing.tuv"), "{e}"); let _ = std::fs::remove_dir_all(&dir); } + +/// #3084, #2096: Export for Screens writes JPGs a strict reader opens, in every colour model and at +/// the qualities and scales the reports used. A four-component (CMYK) file has no JFIF segment, +/// which describes only one- and three-component images (#3140); RGB and gray files keep it. +#[test] +fn export_for_screens_jpgs_open_in_every_colour_model() { + let mut s = session(100.0, 80.0, 1); + s.execute("paint.setFill", &json!({"color": "#cc3300"})).unwrap(); + s.execute("shape.rectangle", &json!({"x": 10, "y": 10, "width": 60, "height": 40})).unwrap(); + for (model, components) in [("rgb", 3), ("cmyk", 4), ("gray", 1)] { + for quality in [100, 80, 50] { + let r = s + .execute( + "document.exportForScreens", + &json!({"formats": [{"format": "jpg"}, {"format": "jpg", "scale": 2}], "settings": {"jpg": {"colorModel": model, "quality": quality}}}), + ) + .unwrap(); + let files = r["files"].as_array().unwrap(); + assert_eq!(files.len(), 2, "{model} {quality}: {r}"); + for (f, width) in files.iter().zip([100, 200]) { + let bytes = b64(f); + let what = format!("{model} q{quality} {}", f["name"]); + assert_eq!(bytes.get(..2), Some(&[0xFF, 0xD8][..]), "{what}: starts with SOI"); + let jfif = bytes.get(2..4) == Some(&[0xFF, 0xE0][..]); + assert_eq!(jfif, components != 4, "{what}: JFIF only on one- and three-component files"); + let image = image::load_from_memory(&bytes).unwrap_or_else(|e| panic!("{what}: {e}")); + assert_eq!(image.width(), width, "{what}"); + } + } + } +}